Reciprocating grate cooler

Abstract

The invention relates to a reciprocating grate cooler in which the drive arrangement is enclosed by a drive housing, the interior of which is closed off so as to be airtight against the atmosphere, but by contrast has a pressure equalization connection to the interior of the cooler housing. Such a reciprocating grate cooler is distinguished by a substantially reduced expenditure for the sealing of the cooler housing and a high degree of freedom from disruption.

I claim: 
     
       1. A reciprocating grate cooler construction having a cooler housing under positive air pressure; a drive mechanism external of said housing and having a reciprocable drive shaft extending through an elongate opening in a side wall of said cooler housing; an air tight drive housing enclosing said drive mechanism and encircling said shaft, said drive housing being in communication with the interior of said cooler housing via said opening; and a pressure equalization connection coupling said drive housing to said cooler housing at said opening to enable substantially equal pressure to be maintained within said cooler housing and said drive housing. 
     
     
       2. The construction according to claim 1 wherein said pressure equalization connection comprises a labyrinth seal. 
     
     
       3. The construction according to claim 2 wherein said labyrinth seal comprises at least two sealing elements fixed on said shaft for movement therewith and at least one stationary sealing element fixed to said side wall of said cooler housing. 
     
     
       4. The construction according to claim 3 wherein said drive housing includes a hopper at a level below that of said labyrinth seal and in communication with the interior of said cooler housing and through which dust falling from the labyrinth seal may be returned to the interior of said cooler housing. 
     
     
       5. The construction according to claim 2 including a guard plate overlying said labyrinth seal and positioned within said cooler housing. 
     
     
       6. The construction according to claim 2 wherein said labyrinth seal comprises interleaved sealing elements carried by said drive shaft and said cooler housing, said sealing elements being adjacent and spaced from one another a distance to provide a substantially dust tight, but not air tight, seal. 
     
     
       7. The construction according to claim 1 wherein said drive housing includes at least one transparent window.